Best Medical Therapy for asymptomatic carotid disease Richard Bulbulia Consultant Vascular Surgeon and Co-PI ACST-2 MRC Population Health Research Unit CTSU, Nuffield Department of Population Health University of Oxford
Italian ACST-2 Collaborators Meeting Martedi 0730 (!) Sala Europa
3 choices for asymptomatic carotid stenosis
3 choices for asymptomatic carotid stenosis ACST-2
Carotid Guidelines 2017
Use Triple Medical Therapy to Prevent MI & Stroke 1. Anti-platelet agents 2. Anti-hypertensive agents 3. Statins to lower LDL-C
Anti-platelet Therapy 75 mg aspirin (or 75 mg clopidogrel if aspirin intolerant)
Anti-platelet agents Intensive anti-thrombotic therapy in acute disease Mono-therapy (aspirin) favoured for secondary prevention Aspirin not recommended for primary prevention bleeding risks outweigh any potential benefits aspirin has not been shown to prevent stroke in primary prevention Asymptomatic carotid patients = primary prevention? Annual risk of CV event >3% per annum, so a carotid stenosis can be considered a CHD risk equivalent
Effects of antiplatelet therapy on MI and Stroke in high-risk patients Category APT CTRL Reduction Prior MI 13.5% 17.0% 25%±4 Acute MI 10.4% 14.2% 30%±4 Prior stroke/tia 17.8% 21.4% 22%±4 Acute stroke 8.2% 9.1% 11%±3 Other high risk 8.0% 10.2% 26%±3 All except acute stroke 11.7% 14.8% 25%±2 All trials 10.7% 13.2% 22%±2 0.0 0.5 1.0 1.5 2.0 (p<0.0001) ATTC
CAPRIE: Clopidogrel v Aspirin (secondary prevention) Clopidogrel: ARR = 0.5%; RRR 8.7% (P=0.043)
Anti-hypertensive Therapy Aim for BP < 140/80
How important is blood pressure to vascular death? 20 mmhg drop in systolic BP halves vascular mortality at 35-69 Prospective Studies Collaboration (1 million adults) PSC, Lancet 2002; 360: 1903
LDL-C Lowering Intensive statin therapy 40-80 mg atorvastatin or 20-40 mg rosuvastatin (Irrespective of baseline lipid profile)
How important are blood lipids? Good statin regimen reduces LDL cholesterol by 2 mmol/l and vascular risk by 40% (Non-vascular mortality is unaffected) CTT, Lancet; online Nov 9, 2010
Proportional effects on MAJOR VASCULAR EVENTS per mmol/l reduction in LDL cholesterol No. of events (% pa) Statin/more statin Control/less statin Relative risk (CI) Nonfatal MI CHD death Any major coronary event 3485 (1.0) 1887 (0.5) 5105 (1.4) 4593 (1.3) 2281 (0.6) 6512 (1.9) 0.73 (0.69-0.78) 0.80 (0.74-0.87) 0.76 (0.73-0.78) CABG PTCA Unspecified Any coronary revascularisation 1453 (0.4) 1767 (0.5) 2133 (0.6) 5353 (1.5) 1857 (0.5) 2283 (0.7) 2667 (0.8) 6807 (2.0) 0.75 (0.69-0.82) 0.72 (0.65-0.80) 0.76 (0.70-0.82) 0.75 (0.72-0.78) Ischaemic stroke Haemorrhagic stroke Unknown stroke Any stroke 1427 (0.4) 257 (0.1) 618 (0.2) 2302 (0.6) 1751 (0.5) 220 (0.1) 709 (0.2) 2680 (0.8) 0.79 (0.72-0.87) 1.12 (0.88-1.43) 0.88 (0.76-1.01) 0.84 (0.79-0.89) Any major vascular event 10973 (3.2) 13350 (4.0) 0.78 (0.76-0.80) 99% or 95% CI CTTC: Lancet 2010; 376 0.4 0.6 0.8 1 1.2 1.4 Statin/more statin better Control/less statin better
Proportional effects on MAJOR VASCULAR EVENTS per mmol/l reduction in LDL cholesterol No. of events (% pa) Statin/more statin Control/less statin Relative risk (CI) Nonfatal MI CHD death Any major coronary event CABG PTCA Unspecified Any coronary revascularisation Ischaemic stroke Haemorrhagic stroke Unknown stroke Any stroke 3485 (1.0) 1887 (0.5) 5105 (1.4) 2133 (0.6) 5353 (1.5) 1427 (0.4) 257 (0.1) 618 (0.2) 2302 (0.6) 4593 (1.3) 2281 (0.6) 6512 (1.9) 21% reduction 1453 (0.4) in 1857 ischaemic (0.5) stroke 1767 (0.5) 2283 (0.7) per mmol/l reduction in LDL-C 2667 (0.8) 6807 (2.0) 1751 (0.5) 220 (0.1) 709 (0.2) 2680 (0.8) 0.73 (0.69-0.78) 0.80 (0.74-0.87) 0.76 (0.73-0.78) 0.75 (0.69-0.82) 0.72 (0.65-0.80) 0.76 (0.70-0.82) 0.75 (0.72-0.78) 0.79 (0.72-0.87) 1.12 (0.88-1.43) 0.88 (0.76-1.01) 0.84 (0.79-0.89) Any major vascular event 10973 (3.2) 13350 (4.0) 0.78 (0.76-0.80) 99% or 95% CI CTTC: Lancet 2010; 376 0.4 0.6 0.8 1 1.2 1.4 Statin/more statin better Control/less statin better
Statins and carotid-related stroke MRC/BHF Heart Protection Study (HPS) Allocation to statin halved rate of CEA 42 [0.4%] statin vs 82 [0.8%] placebo; P=0.0003
Effects of intensive statin therapy on stroke Lower LDL-C is better Residual risk of stroke persists despite intensive medical therapy
New developments Anti-thrombotic therapy COMPASS (2.5 mg rivaroxaban + aspirin v aspirin alone) Risk of stroke halved Blood pressure lowering therapy SPRINT (low v very low BP targets) 121 mmhg v 136 mmhg SBP (15mmHg) for 3 years 25% reduction in MVE Doubling of SAE due to study intervention: 220 [4.7%] v 118 [2.5%], largely driven by acute renal failure Lipid-lowering therapy: PCSK-9 Inhibition FOURIER (Evolocumab) 23% reduction in risk of stroke
Triple medical therapy effective Aspirin reduces CV risk by around 20%, but effect on stroke unclear
Triple medical therapy effective Aspirin reduces CV risk by around 20%, but effect on stroke unclear? Aim for lower SBP to prevent CV events (but at a cost) 120/80?
Triple medical therapy effective Aspirin reduces CV risk by around 20%, but effect on stroke unclear? Aim for SBP ~120 mmhg to prevent CV events (but at a cost) Intensive LDL lowering safe and effective
Triple medical therapy effective, but residual risk remains Aspirin reduces CV risk by around 20%, but effect on stroke unclear? Aim for SBP ~120 mmhg to prevent CV events (but at a cost) Intensive LDL lowering safe and effective Carotid intervention halves any residual risk VA, ACAS & ACST-1 IPD (restricted triple medical therapy)